Fluid pressure system



Nov. 8, 193s. w. JQCONERY Em. 25135962 y FLUID PRESSURE`SYSTEM Filed March 18, 1937 structure 9.

chamber III into which the water from ythe pump- 'I'hreaded into one side Patented Nov. 8, 1938 UNITED' STATI-:sw

PATENT OFFICE a ansatz FLUID PRESSURE SYSTEM William J. Conery and Albert Nelson, San Jose, Calif Application March 1s, 1937, serial Nu. 131,668 1 claim.; (ci. 10s- 6) rIhe system herein disclosed is primarily vfor the purpose of automatically maintaining water "under a given pressure through the medium of an air cushion in a closed tank when the water is supplied to the tank by a centrifugal pump.

f -It is', therefore, one object of the present invention to provide means whereby a centrifugal pump may be used to supply water to the tank and at the same time automatically maintainthe 10 desired air pressure therein.

In the particular assembly herein disclosedwe' show at I a portion of a centrifugal pump having a discharge at 2, and a portion of a pressure tank a5 ,at havinga `water supply pipe at and an` lair cushion chamber at 5 above the water level 0, an

automatic excess pressure air exhaust vbeing indicated at 1. f 4 4In the pipe line l connecting the -pump dis- 80 charge 2 and the tank inlet l is inserted a valve This valve structure comprisesqa passes as indicated at I I. of the chamber wall Il is -a Venturi tube I3 conas nected to the supply pipe l. Y.

In the throat Il ofthe Venturi tube is formed a I! communicating with an air inlet v valve I0 threaded into the side of the tube "as at] I1. The valve I as shown is a commercial prod- 40 uct'known as the Schrader valve and is adjusted to readily permit air to bedrawn into the tube I3 but will effectually prevent the discharge of air orwater therefrom'. f At II is a needle extending into the throat Il and axially adjustable relative thereto through the medium of its threaded engagement at I9 with the wall I2. vLeakage is -prevented at 'this point by the packingnut 20. l

The needle I8 is provided with a handle 2| by means of which it may b e operated, and it is alsoprovidedwitha n extendinglength.

wise therethrough and tted with a Schrader valve in its outer end as at 23.

When the water delivered by the centrifugal pump I passes through the throat Il its velocity is increasedlv of course, and an aspirator is formed by means of which air is introduced into the tube and tank through the valve I6. The velocity of the water, and consequently the amount of air introduced through valve I8, is

governed. or controlled by adjustment of the 10 It should now be clear that the adjustable features of the system may be so set that 'a desired pressure can be maintained in tank 3 at allk times. When the pressure in the tank is built up to the higher limit the back pressure will hold the Schrader valve closed and no air can be ini troduced, and of course excess air will discharge at 1. When the pressure inthe tank drops ben low. the lower limit the internal pressure on the 90 Schrader valve is reduced and air is introducedl as described. In a system of this kind some variation in pressure is permitted of course, say a differential of some ten pounds between the high vand iowpressure limits. While two Schrader valves Aare' herein shown as supplying air to the tube and tank either one may be dispensed with and one alone used.

It is to be understood of course, that while we khave shown but one specific embodiment of the invention. changes in form,` construction, and method of lassembly and operation may be made withinthe scope of the appended claim.

We claim:

In a system of the haracter described, the 35 combination with a centrifugal pump,`a water l tank having an air cushion chamber therein, and` a pipe leading from the pump to discharge'into the tank; of an automatic spring-'pressed-valve controlled air aspirator inserted in thel pipe 40 whereby reduction of air pressure in thetank -below` a predetermined'point will. increase the velocity of fiowof water through the aspirator and A thereby induct air through the valve into the pipe o and tank,l` and increase of' air pressure in the 45 tank to a predetermined point willbuild up' a back-pressure of water in the pipe to close the valv'e.

'wmmAM J. connnr. amasar NmsoN. 

